The type of panels dealt with in this invention comprises a substrate forming the panel body, generally in a molded foam or thermoplastic material upon the surface of which a skin or similar element is placed for primarily decorative purposes (in a synthetic material with the required surface appearance) showing a linear visual structure characteristic which corresponds to a functional line of the construction or assembly.
Through the applicant's document, EP-A-1 334.818, incorporated herein by reference in its entirety, a new improved process is made known by which several preformed sections of skin are produced (by forming or molding), which are intended to form the constituent parts of a given decorative skin. These sections are then sewn together to form the decorative skin, before the aforementioned skin is placed on a substrate which forms the body of the panel by one of the fastening modes described previously.
This process presents the disadvantage of requiring many stages, some of which are not automated and require manual intervention, which involves a high cost and generates a relatively significant rate of waste, which therefore makes it impossible to guarantee a rigorous standardization.
Moreover, it proves interesting, and improves the aesthetic aspect of the panel at the area where the two skins are assembled, to have one or several seam lines. These should be parallel to the assembly line. However, the processes known to date do not make it possible to systematically guarantee obtaining this type of line or perfectly parallel seam lines at the point where the two skins are assembled to form the functional construction or assembly line.
Moreover, in the currently known processes, it is necessary to first sew the assembly seam to connect the skins one to the other. However, this seam may involve deformations or folds, and thus, a degraded appearance.
Moreover, it is generally also necessary to fold or stitch back and then glue the edges (commonly indicated under the end of the rearmost part of the seam) of the parts making up the skins after their assembly. However, this stage is manual and does not guarantee a consistent fold strip, so the visual aspect of the visible surface of the skin is often degraded.